The invention concerns a method for the gasification of coke in connection with chamber coking.
In coke gasification, depending on different applications of the gas in the various industrial sectors, either a lean gas or a generator gas or a water gas or a synthetic gas can be produced. The lean or generator gas is produced with air as a gasifying agent, and contains carbon monoxide, hydrogen, small amounts of carbon dioxide, and about 45 to 65% nitrogen, while water gas is produced through the gasification of coal with steam and contains about 40% carbon monoxide and 50% hydrogen.
Water gas is usually produced in an alternating operation, by alternately "hot blowing" air in a fuel layer and alternately treating so called gas or "cold blowing" with steam. These discontinuous gasification methods involve large temperature fluctuations during cold and hot blowing which result in change-over problems. Continuous methods are known wherein steam and air or oxygen are introduced sumultaneously into the coke charge, and a mixed gas is produced (see Grosskinsky, Handbuch des Kokereiwesens (Handbook of Coking) vol. 1, p. 357 ff.).
In all methods for the gasification of high-temperature coke, the coke to be gasified is commonly introduced into the gasifier, in a cold (unheated) state. Moreover, such methods require significant amounts of thermal energy to initially heat the gasifier to operating temperature.
Subjecting the coal to low-temperature carbonization prior to the gasification proper is known in coke gasification methods wherein a carbonization shaft is attached on the gasification reactor proper, and the heat of carbonization is introduced through a partial current of the hot manufactureed gas (see Ullmann, vol. 10, 1958, p. 388 and p. 427). However, the output of this generator (with the carbonization attachment) is substantially lower due to the lower stability of the carbonized fuel, as compared to high temperature coke. In addition, the temperature of the low-temperature coke is so low that generation of water gas is not possible without previous heating.